以壓迫性視神經病變表現的嗜鉻細胞瘤腦部轉移-罕見病例報告

謝尚儒¹、陳國鋅²、鐘旭東¹、朱怡靜³

¹亞東紀念醫院 外科部 泌尿科；²亞東紀念醫院 外科部 一般外科; ³亞東紀念醫院 眼科部

Pheochromocytoma with Brain Metastasis Presenting with Compressive Optic Neuropathy--A Rare Case Report

Shang-Ju Hsieh¹, Kuo-Hsin Chen², Shiu- Dong Chung¹, Chu Yi-Ching³

Division of Urology¹ Department of Surgery, Far Eastern Memorial Hospital,

 Division of General surgery², Department of Surgery, Far Eastern Memorial Hospital,  Department of Ophthalmology³, Far Eastern Memorial Hospital

Introduction: Pheochromocytomas and paragangliomas are rare tumors that share the same histological findings; they can only be distinguished by their anatomical location. While pheochromocytomas and paragangliomas are the most benign neoplasms, 10% of pheochromocytomas were reported to be malignant based on evidence of metastasis at presentation or later. Herein, we report the case of a 60-year-old man with a metastatic pheochromocytoma in the left orbital apex and cavernous sinus, which resulted in loss of vision in the left eye. We believe that, to our knowledge, this is the first case of a pheochromocytoma with involvement of the optic nerve in our institution for the past twenty years.

Case presentation: A 60-year-old man presented to the emergency department with a complaint of sudden loss of vision in the left eye. He reported a left temporal headache since the morning. He denied any family history; no previous medical history was noted. His blood pressure was 198/118 mmHg, pulse rate 87 beats/min, and respiratory rate 19 breaths/min. On physical examination, the left eye showed no perception of light. All laboratory test results were within the normal range. Computed tomography of the brain showed no subdural hematoma, subarachnoid hemorrhage, or intracerebral hemorrhage. Nevertheless, magnetic resonance imaging (MRI) of the head and orbit obtained after intravenous administration of contrast material showed a 2.0-cm lobulated lesion in the left orbital apex and cavernous sinus. Differential diagnosis suggested an abscess from sphenoid sinusitis and tuberculosis. Fluid accumulation along the left optic nerve was observed on imaging, and secondary inflammation was suspected. Chest computed tomography to exclude pulmonary tuberculosis incidentally revealed a huge right suprarenal mass. Repeated liver tri-phase CT showed a 12.4 × 9.6 × 12.1-cm right suprarenal tumor with invasion of the right posterior liver. Adrenocortical carcinoma and pheochromocytoma were suspected. Therefore, the patient underwent laparoscopic right adrenalectomy and S7 segmental hepatectomy uneventfully. Immunohistochemically, the tumor was consistent with a pheochromocytoma; the adjacent liver was directly involved. Subsequently, iodine-131 metaiodobenzylguanidine (MIBG) scintigraphy confirmed metastasis of the left orbital apex region, which causes compressive optic neuropathy.